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61.
Twelve horses suffering from navicular bone disease were examined in a prospective, controlled histomorphometric study for six months. The objective was to compare the histology of navicular bones from untreated animals to those treated with the egg-bar shoeing technique. These data were compared to similar sections from three normal animals. The current investigation provided quantitative support to previous findings concerning clinical improvement. Detailed histology, changes in bone morphometry and pathophysiological reactions are discussed. 相似文献
62.
Color dilution in the gray collie 总被引:1,自引:0,他引:1
63.
64.
65.
Mink were vaccinated against canine distemper and challenged with the Snyder Hill strain of canine distemper virus. Protection was acquired if vaccination took place more than a few days before challenge. If vaccination took place even early during incubation mortality was higher than in the unvaccinated controls. Full protection of kits may be achieved even at an age of 16 to 20 days provided the kits had not passively acquired immunity from their mothers. Kits surviving distemper because of passively acquired immunity may not actively acquire immunity during infection and may die at a later exposure. 相似文献
66.
M. Lund 《EPPO Bulletin》1977,7(2):503-508
The comparatively few newly developed rodenticides are mentioned, and their effectiveness against warfarin-resistant rats and mice is discussed. Two compounds, an acute poison and an anticoagulant, seem to be more promising than others. 相似文献
67.
Cellular localization of somatomedin (insulin-like growth factor) messenger RNA in the human fetus 总被引:49,自引:0,他引:49
The somatomedins or insulin-like growth factors (IGFs) are synthesized in many organs and tissues, but the specific cells that synthesize them in vivo have not been defined. By in situ hybridization histochemistry, IGF I (somatomedin C) and IGF II messenger RNAs were localized to connective tissues or cells of mesenchymal origin in 14 organs and tissues from human fetuses. IGF messenger RNAs were localized to perisinusoidal cells of liver, to perichondrium of cartilage, to sclera of eye, and to connective tissue layers, sheaths, septa, and capsules of each organ and tissue. All of the hybridizing regions are comprised predominantly of fibroblasts or other cells of mesenchymal origin. Because these cells are widely distributed and anatomically integrated into tissues and organs, they are ideally located for production of IGFs, which may exert paracrine effects on nearby target cells. 相似文献
68.
Viacheslav I. Adamchuk Eric D. Lund Todd M. Reed Richard B. Ferguson 《Precision Agriculture》2007,8(3):139-149
Since conventional sampling and laboratory soil analysis do not provide a cost effective capability for obtaining geo-referenced
measurements with adequate frequency, different on-the-go sensing techniques have been attempted. One such recently commercialized
sensing system combines mapping of soil electrical conductivity and pH. The concept of direct measurement of soil pH has allowed
for a substantial increase in measurement density. In this publication, soil pH maps, developed using on-the-go technology
and obtained for eight production fields in six US states, were compared with corresponding maps derived from grid sampling.
It was shown that with certain field conditions, on-the-go mapping can significantly increase the accuracy of soil pH maps
and therefore increase the potential profitability of variable rate liming. However, in many instances, these on-the-go measurements
need to be calibrated to account for a field-specific bias. After calibration, the overall error estimate for soil pH maps
produced using on-the-go measurements was less than 0.3 pH, while non-calibrated on-the-go and conventional field average
and grid-sampling maps produced errors greater than 0.4 pH. 相似文献
69.
Inhibition of calcification of bioprosthetic heart valves by local controlled-release diphosphonate 总被引:8,自引:0,他引:8
R J Levy J Wolfrum F J Schoen M A Hawley S A Lund R Langer 《Science (New York, N.Y.)》1985,228(4696):190-192
Bioprostheses fabricated from porcine aortic valves are widely used to replace diseased heart valves. Calcification is the principal cause of the clinical failure of these devices. In the present study, inhibition of the calcification of bioprosthetic heart valve cusps implanted subcutaneously in rats was achieved through the adjacent implantation of controlled-release matrices containing the anticalcification agent ethanehydroxydiphosphonate dispersed in a copolymer of ethylene-vinyl acetate. Prevention of calcification was virtually complete, without the adverse effects of retarded bone and somatic growth that accompany systemic administration of ethanehydroxydiphosphonate. 相似文献
70.
Monkeys whose optic chiasm and forebrain commissures had been sectioned and control monkeys with only the optic chiasm cut were tested for interocular transfer of discriminations based on direction of movement. Only the control animals showed transfer to the untrained eye, which suggests that discrimination of movement, like pattern, is a function strongly dependent on the cortex. 相似文献